WAVELENGTH VARIABLE FILTER SYSTEM

摘要

PROBLEM TO BE SOLVED: To keep the incident angle of reflected light always constant in changing a wavelength by changing the rotating angle of an optical band-pass filter and to enhance selectivity of reflection. SOLUTION: The filter system is provided with a parallel rocking section 15 consisting of an optical filter 13 and a mirror 14. Incident light is made incident on the mirror and the optical filter 13 and is reflected via the mirror 14. The reflected light is reflected again by the mirror 17 at the optical axis as it is and is further reflected by the mirror 14 and is added to the optical filter 13. The incident angle is changed by rotating the rocking section 15 via a turning shaft 16 and can be received at the same axis. COPYRIGHT: (C)2004,JPO